Emily Dickinson Lexicon

TARN-ISH, v.t. [Fr. ternir, ternissant.]

1. To sully; to soil by an alteration induced by the air, or by dust and the like; to diminish or destroy luster; as, to tarnish a metal; to tarnish gilding; to tarnish the brightness or beauty of color.
2. To diminish or destroy the purity of; as, to tarnish reputation or honor.